Concrete infrastructure represents an enormous investment of materials,
energy, and capital, and results in significant environmental burdens
and social costs. There is an ongoing effort to identify material
alternatives to conventional concrete. Life cycle assessment (LCA) is an
important tool to evaluate the environmental performance of alternative
infrastructure materials and systems. Here, we present a comparative
LCA of two bridge deck systems over a 60 year service life: one using
conventional steel expansion joints and the other based on a link slab
design using a concrete alternative, engineered cementitious composites
(ECC). The ECC link slab design is expected to extend the bridge deck
service life and reduce maintenance activities. A life cycle model was
developed that accounts for materials production and distribution,
construction and maintenance processes, construction-related traffic
congestion, and end-of-life management. Results indicate that the ECC
bridge deck system has significant advantages in environmental
performance: 40% less life cycle energy consumption, 50% less solid
waste generation, and 38% less raw material consumption. Construction
related traffic congestion is the greatest contributor to most life
cycle impact categories.